[ ir-i-vur-suh-buhl ]
See synonyms for irreversible on
  1. not reversible; incapable of being changed: His refusal is irreversible.

Origin of irreversible

First recorded in 1620–30; ir-2 + reversible

Other words from irreversible

  • ir·re·vers·i·bil·i·ty, ir·re·vers·i·ble·ness, noun
  • ir·re·vers·i·bly, adverb

Words Nearby irreversible Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use irreversible in a sentence

British Dictionary definitions for irreversible


/ (ˌɪrɪˈvɜːsəbəl) /

  1. not able to be reversed: the irreversible flow of time

  2. not able to be revoked or repealed; irrevocable

  1. chem physics capable of changing or producing a change in one direction only: an irreversible reaction

  2. thermodynamics (of a change, process, etc) occurring through a number of intermediate states that are not all in thermodynamic equilibrium

Derived forms of irreversible

  • irreversibility or irreversibleness, noun
  • irreversibly, adverb

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012